Local-Area-Enhanced, 2.5-Meter Resolution Natural-Color and 
Color-Infrared Satellite-Image Mosaics of the Herat Mineral 
District in Afghanistan

By Philip A. Davis[1], Scott A. Arko[2], and 
Michelle L. Harbin[2]

[1]U.S. Geological Survey

[2]University of Alaska Fairbanks, Alaska Satellite 
Facility


Data Series 709-T

2013

U.S. Department of the Interior
U.S. Geological Survey


Abstract:

The U.S. Geological Survey (USGS), in cooperation with the 
U.S. Department of Defense Task Force for Business and 
Stability Operations, prepared databases for mineral-
resource target areas in Afghanistan. The purpose of the 
databases is to (1) provide useful data to ground-survey 
crews for use in performing detailed assessments of the 
areas and (2) provide useful information to private 
investors who are considering investment in a particular 
area for development of its natural resources. The set of 
satellite-image mosaics provided in this Data Series (DS) 
is one such database. Although airborne digital color-
infrared imagery was acquired for parts of Afghanistan in 
2006, the image data have radiometric variations that 
preclude their use in creating a consistent image mosaic 
for geologic analysis. Consequently, image mosaics were 
created using ALOS (Advanced Land Observation Satellite; 
renamed Daichi) satellite images, whose radiometry has been 
well determined (Saunier, 2007a,b). This part of the DS 
consists of the locally enhanced ALOS image mosaics for the 
Herat mineral district, which has barium and limestone 
deposits.

ALOS was launched on January 24, 2006, and provides 
multispectral images from the AVNIR (Advanced Visible and 
Near-Infrared Radiometer) sensor in blue (420-500 
nanometer, nm), green (520-600 nm), red (610-690 nm), and 
near-infrared (760-890 nm) wavelength bands with an 8-bit 
dynamic range and a 10-meter (m) ground resolution. The 
satellite also provides a panchromatic band image from the 
PRISM (Panchromatic Remote-sensing Instrument for Stereo 
Mapping) sensor (520-770 nm) with the same dynamic range 
but a 2.5-m ground resolution. The image products in this 
DS incorporate copyrighted data provided by the Japan 
Aerospace Exploration Agency ((c)JAXA,2007,2008,2009), but 
the image processing has altered the original pixel 
structure and all image values of the JAXA ALOS data, such 
that original image values cannot be recreated from this 
DS. As such, the DS products match JAXA criteria for value 
added products, which are not copyrighted, according to the 
ALOS end-user license agreement. 

The selection criteria for the satellite imagery used in 
our mosaics were images having (1) the highest solar-
elevation angles (near summer solstice) and (2) the least 
cloud, cloud-shadow, and snow cover. The multispectral and 
panchromatic data were orthorectified with ALOS satellite 
ephemeris data, a process which is not as accurate as 
orthorectification using digital elevation models (DEMs); 
however, the ALOS processing center did not have a precise 
DEM. As a result, the multispectral and panchromatic image 
pairs were generally not well registered to the surface and 
not coregistered well enough to perform resolution 
enhancement on the multispectral data. For this particular 
area, PRISM image orthorectification was performed by the 
Alaska Satellite Facility, applying its photogrammetric 
software to PRISM stereo images with vertical control 
points obtained from the digital elevation database 
produced by the Shuttle Radar Topography Mission (Farr and 
others, 2007) and horizontal adjustments based on a 
controlled Landsat image base (Davis, 2006). The 10-m AVNIR 
multispectral imagery was then coregistered to the 
orthorectified PRISM images and individual multispectral 
and panchromatic images were mosaicked into single images 
of the entire area of interest. The image coregistration 
was facilitated using an automated control-point algorithm 
developed by the USGS that allows image coregistration to 
within one picture element. Before rectification, the 
multispectral and panchromatic images were converted to 
radiance values and then to relative-reflectance values 
using the methods described in Davis (2006). Mosaicking the 
multispectral or panchromatic images started with the image 
with the highest sun-elevation angle and the least 
atmospheric scattering, which was treated as the standard 
image. The band-reflectance values of all other 
multispectral or panchromatic images within the area were 
sequentially adjusted to that of the standard image by 
determining band-reflectance correspondence between 
overlapping images using linear least-squares analysis. The 
resolution of the multispectral image mosaic was then 
increased to that of the panchromatic image mosaic using 
the SPARKLE logic, which is described in Davis (2006). Each 
of the four-band images within the resolution-enhanced 
image mosaic was individually subjected to a local-area 
histogram stretch algorithm (described in Davis, 2007), 
which stretches each band's picture element based on the 
digital values of all picture elements within a 1,000-m 
radius. The final databases, which are provided in this DS, 
are three-band, color-composite images of the local-area-
enhanced, natural-color data (the blue, green, and red 
wavelength bands) and color-infrared data (the green, red, 
and near-infrared wavelength bands).

All image data were initially projected and maintained in 
Universal Transverse Mercator (UTM) map projection using 
the target area's local zone (41 for Herat) and the WGS84 
datum. The final image mosaics were subdivided into eight 
overlapping tiles or quadrants because of the large size of 
the target area. The eight image tiles (or quadrants) for 
the Herat area are provided as embedded geotiff images, 
which can be read and used by most geographic information 
system (GIS) and image-processing software. The tiff world 
files (tfw) are provided, even though they are generally 
not needed for most software to read an embedded geotiff 
image. Within the Herat study area, one subarea was 
designated for detailed field investigations (that is, the 
Barium-Limestone subarea); this subarea was extracted from 
the area's image mosaic and is provided as separate 
embedded geotiff images.

Disclaimer:

Although these data have been processed successfully on a 
computer system at the U.S. Geological Survey, no warranty 
expressed or implied is made regarding the display or 
utility of the data on any other system, or for general or 
scientific purposes, nor shall the act of distribution 
constitute any such warranty. The U.S. Geological Survey 
shall not be held liable for improper or incorrect use of 
the data described and (or) contained herein.

Contact Information:

If you have any questions regarding this dataset please 
feel free to contact:
Philip A. Davis, Research Geologist
U.S. Geological Survey
2255 North Gemini Drive, Building 4
Flagstaff, AZ 86001
pdavis@usgs.gov
(928) 556-7084

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This Data Series includes the following Information. 
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DIRECTORY

index_maps

Herat_Area-of-Interest_Index_Map.pdf -- Index map stored in 
Adobe Acrobat (PDF) format displaying the location of the 
Herat mineral district within Afghanistan in the geographic 
coordinate system. Index map is also provided in jpeg 
format.

Herat_Image_Index_Map.pdf -- Index map of the image 
products showing the extent of the target area and tile or 
quadrant scheme that was used to subdivide the image 
mosaics for the target area. The target area includes one 
subarea for detailed investigation (the Barium-Limestone 
subarea), whose boundary is also depicted. This information 
is displayed on the topographic shaded-relief base map of 
Bohannon (2007a-c) in the UTM map projection and stored in 
both PDF and jpeg formats.

image_files

Local-area-enhanced, 2.5-m natural-color and color-infrared 
satellite-image mosaics in geotiff format with their tfw 
files. All images with their tfw and metadata files are 
compressed with standard file compression software to 
facilitate file transfer.

metadata

HERAT_UTM_WGS84_Z41_NC_Qx.tif.txt -- FGDC compliant 
metadata files for each image tile or quadrant (designated 
by Qx). NC designates natural-color image data.

HERAT_UTM_WGS84_Z41_CIR_Qx.tif.txt -- FGDC compliant 
metadata files for each image tile or quadrant (designated 
by Qx). CIR designates color-infrared image data. 

HERAT_BARIUM-LIMESTONE_SUBAREA_UTM_WGS84_Z41_NC.tif.txt -- 
FGDC compliant metadata file for the subarea image. NC 
designates natural-color image data.

HERAT_BARIUM-LIMESTONE_SUBAREA_UTM_WGS84_Z41_CIR.tif.txt -- 
FGDC compliant metadata file for the subarea image. CIR 
designates color-infrared image data.

shapefiles

Herat_Image_Mosaic_Index.shp -- A shapefile showing the 
boundary for the area of interest, as well as its subarea.

index.html -- http://pubs.usgs.gov/ds/709/t/

1_readme.txt -- This file.

References Cited:

Bohannon, R.G., 2007a, Topographic map of quadrangle 3560 
and 3562, Sir Band (402), Khawja-Jir (403), and Bala-
Murghab (404) quadrangles, Afghanistan: U.S. Geological 
Survey Open-File Report 2005-1098-B, 1:250,000 scale, 
available at http://pubs.usgs.gov/of/2005/1098/B/. 

Bohannon, R.G., 2007b, Topographic map of quadrangles 3460 
and 3360, Kol-i-Namaksar (407), Ghuryan (408), Kawir-i-
Naizar (423), and Kohe-Mahmudo-Esmailjan (414) quadrangles, 
Afghanistan: U.S. Geological Survey Open-File Report 2005-
1103-B, 1:250,000 scale, available at 
http://pubs.usgs.gov/of/2005/1103/B/.

Bohannon, R.G., 2007c, Topographic map of quadrangle 3462, 
Herat (409) and Chesht-Sharif (410) quadrangles, 
Afghanistan: U.S. Geological Survey Open-File Report 2005-
1104-B, 1:250,000 scale, available at 
http://pubs.usgs.gov/of/2005/1104/B/.

Davis, P.A., 2006, Calibrated Landsat ETM+ nonthermal-band 
image mosaics of Afghanistan: U.S. Geological Survey Open-
File Report 2006-1345, 18 p., available at 
http://pubs.usgs.gov/of/2006/1345/.

Davis, P.A., 2007, Landsat ETM+ false-color image mosaics 
of Afghanistan: U.S. Geological Survey Open-File Report 
2007-1029, 22 p., available at 
http://pubs.usgs.gov/of/2007/1029/.

Farr, T.G., Rosen, P.A., Caro, E., Crippen, R., Duren, R., 
Hensley, S., Kobrick, M., Paller, M., Rodriguez, E., Roth, 
L., Seal, D., Shaffer, S., Shimada, J., Umland, J., Werner, 
M., Oskin, M., Burbank, D., and Alsdorf, D., 2007, The 
Shuttle Radar Topography Mission: Reviews of Geophysics, v. 
45, RG2004, 33 p., doi:10.1029/2005RG000183.

Saunier, S., 2007a, Final calibration/validation report, 
PRISM: GAEL Consultant report, 27 p., accessed April 23, 
2012, at http://earth.esa.int/pub/ESA_DOC/ALOS011.pdf.

Saunier, S., 2007b, Final calibration/validation report, 
AVNIR-2: GAEL Consultant report, 25 p., accessed April 23, 
2012, at http://earth.esa.int/pub/ESA_DOC/ALOS012.pdf.